A year of pent-up frustration and anger finally erupted in public when former minister Andrew Mitchell accused the police officer at the heart of the "plebgate" affair of telling lies which destroyed his career.

In an extraordinary press conference, the former government chief whip, who was forced to quit after he was accused by Downing Street police of swearing at them and calling them "plebs", said he had been "stitched up".

"My reputation was destroyed. I was vilified... my family and I were driven from my home. I was spat at in the street," he said.

And all because police officer Toby Rowland lied about the 49-second incident, he said. And he pledged to force the officer to give evidence in court under oath in a libel trial against the Sun newspaper which ran the original story.

"I have told the truth, the police have not. I wish now to make clear that PC Toby Roland was not telling the truth. I will seek to tell this on oath in a court of law," he said.

Mitchell spoke out after the Crown Prosecution Service announced there was "insufficient evidence" to pursue action against the officer and that there had not been any conspiracy of misinformation.

Another officer, who claimed to have witnessed the incident, is to be prosecuted for misconduct in public office.

And the Independent Police Complaints Commission has announced that five officers will now face gross misconduct proceedings in relation to the affair and its aftermath, which could lead to their dismissal.

The CPS announced: "Taking it all into account, including the accounts of the officer at the gate of Downing Street and that of Andrew Mitchell MP before, during and after the incident, we have found that there is insufficient evidence to show that the officer at the gate lied in his account.

"The CPS has also found that there is insufficient evidence to show that Mr Mitchell was the victim of a conspiracy of misinformation."

But Mitchell and his ally, former minister David Davis, rejected the CPS findings and presented the CCTV footage of the incident in which Mitchell was stopped from cycling though the Downing Street main gates.

They said they were not impressed with the investigation into the affair and attempted to show that, in a vital five second clip of the incident, it would have been impossible for Mitchell to have used all the words alleged, including calling the officer a "F***ing pleb".

Davis said: "When five officers are facing charges of one sort or another, that's pretty much vindication. But nevertheless, he will still not be pleased that they haven't got to the bottom of the whole thing."

Mitchell has always admitted swearing but flatly denied using the toxic word "pleb".

He has refused to comment in detail in the months following the incident which has escalated, seen officers hauled before Commons committees and led to a major crisis of confidence in the police.

But his anger at the CPS decision not to proceed against Rowland was clear and he has now pledged not to let the matter rest and to ensure the officer is forced to give his account under oath.